frame1.java~267~

我用java写的词法分析器

package 编译技术;

import java.io.*;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/**
 * <p>Title: </p>
 * <p>Description: 词法分析</p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>Company: 边缘开发室</p>
 * @author 谭正辉
 * @version 1.0
 */

public class Frame1
    extends JFrame
{
  JPanel contentPane;
  JScrollPane jScrollPane1 = new JScrollPane();
  JTextArea sourceArea = new JTextArea();
  JButton doButton1 = new JButton();
  JButton quitButton = new JButton();
  //源文件
  String str = null;
  JLabel jLabel1 = new JLabel();
  JScrollPane jScrollPane2 = new JScrollPane();
  JTextArea MessageBox = new JTextArea();
  JMenuBar jMenuBar1 = new JMenuBar();
  JMenu jMenu1 = new JMenu();
  JMenuItem jMenuItem1 = new JMenuItem();
  JMenuItem jMenuItem2 = new JMenuItem();
  ImageIcon image = new ImageIcon("src/image/letterTable.jpg");
  JMenuItem jMenuItem3 = new JMenuItem();
  int row, column, locate; //row为行，column为列
  char[] sourceChar; //要分析的字符数组
  int type; //类型
  //用于存储当前字符串单元
  String tempString;

  ReservedWordTable rwt;

  //用于标识是否通过词法分析，如果通过了，才可以进行语法分析，如果没有，则必须修正提示的错误
  boolean passWordAnalyse=true;
  JButton doButton2 = new JButton();

  //Construct the frame
  public Frame1()
  {
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try
    {
      jbInit();
    }
    catch (Exception e)
    {
      e.printStackTrace();
    }
  }

  //Component initialization
  private void jbInit() throws Exception
  {
    contentPane = (JPanel)this.getContentPane();
    contentPane.setLayout(null);
    this.setJMenuBar(jMenuBar1);
    this.setResizable(false);
    this.setSize(new Dimension(615, 459));
    this.setTitle("词法分析");
    jScrollPane1.setBounds(new Rectangle(8, 14, 448, 222));
    sourceArea.setToolTipText("输入要词法分析的程序源码");
    sourceArea.setLineWrap(true);
    sourceArea.setTabSize(4);
    doButton1.setBounds(new Rectangle(475, 23, 102, 36));
    doButton1.setText("词法分析");
    doButton1.addActionListener(new Frame1_doButton_actionAdapter(this));
    quitButton.setText("退出");
    quitButton.addActionListener(new Frame1_quitButton_actionAdapter(this));
    quitButton.setBounds(new Rectangle(475, 343, 102, 36));
    jLabel1.setText("编译信息如下");
    jLabel1.setBounds(new Rectangle(8, 237, 446, 21));
    MessageBox.setBorder(BorderFactory.createLoweredBevelBorder());
    jScrollPane2.setBounds(new Rectangle(8, 256, 448, 126));
    MessageBox.setBorder(null);
    MessageBox.setText("");
    MessageBox.setEditable(false);
    jMenu1.setText("系统信息");
    jMenuItem1.setText("类别码表");
    jMenuItem1.addActionListener(new Frame1_jMenuItem1_actionAdapter(this));
    jMenuItem2.setText("关于本软件");
    jMenuItem2.addActionListener(new Frame1_jMenuItem2_actionAdapter(this));
    jMenuItem3.setText("打开文件");
    jMenuItem3.addActionListener(new Frame1_jMenuItem3_actionAdapter(this));
    doButton2.setBounds(new Rectangle(475, 177, 102, 36));
    doButton2.setText("语法分析");
    doButton2.addActionListener(new Frame1_jButton1_actionAdapter(this));
    contentPane.add(jScrollPane1, null);
    contentPane.add(jLabel1, null);
    contentPane.add(jScrollPane2, null);
    contentPane.add(quitButton, null);
    contentPane.add(doButton2);
    contentPane.add(doButton1, null);
    jScrollPane2.getViewport().add(MessageBox, null);
    jScrollPane1.getViewport().add(sourceArea, null);
    jMenuBar1.add(jMenu1);
    jMenu1.add(jMenuItem3);
    jMenu1.add(jMenuItem1);
    jMenu1.add(jMenuItem2);
  }

  //Overridden so we can exit when window is closed
  protected void processWindowEvent(WindowEvent e)
  {
    super.processWindowEvent(e);
    if (e.getID() == WindowEvent.WINDOW_CLOSING)
    {
      System.exit(0);
    }
  }

  void quitButton_actionPerformed(ActionEvent e)
  {
    //退出程序
    System.exit(0);
  }

  void doButton_actionPerformed(ActionEvent e)
  {
    MessageBox.setText(" 词法分析结果如下");
    column = row = 1;
    locate = 0;

    //实例化构建Hash表存入保留字的类
    rwt = new ReservedWordTable();
    //获取待编译的字符串并存放在一个字符数组里面
    String source = sourceArea.getText().toString();
    sourceChar = new char[source.length()];
    sourceChar = source.toCharArray();

    while (locate < sourceChar.length)
    {
      //对源程序进行词法分析
      startWordAnalyse();
    }
    MessageBox.setText(MessageBox.getText() + "\n 词法分析完成");
    //保存结果
    saveResult();
  }

  public void startWordAnalyse()
  {
    switch (sourceChar[locate])
    {
      case '+':
      {
        type = 13;
        tempString = "+";
        locate++;
        column++;
        break;
      }
      case '-':
      {
        type = 14;
        tempString = "-";
        locate++;
        column++;
        break;
      }
      case '*':
      {
        type = 15;
        tempString = "*";
        locate++;
        column++;
        break;
      }
      case '/':
      {
        type = 16;
        tempString = "/";
        locate++;
        column++;
        break;
      }
      //：＝
      case ':':
      {
        if (locate != sourceChar.length - 1)
        {
          if (sourceChar[locate + 1] == '=')
          {
            locate++;
            column++;
            type = 17;
            tempString = ":=";
          }
          //：单独出现在中间位置
          else
          {
            type = 1000;
            tempString = ":";
          }
        }
        //：出现在结束位置
        else if (locate == sourceChar.length - 1)
        {
          type = 1000;
          tempString = ":";
        }
        locate++;
        column++;
        break;
      }
      //<=,<>,<
      case '<':
      {
        if (locate != sourceChar.length - 1)
        {
          if ( (sourceChar[locate + 1] != '=') &&
              (sourceChar[locate + 1] != '>'))
          {
            //识别<
            type = 20;
            tempString = "<";
          }
          else if (sourceChar[locate + 1] == '=')
          {
            //识别<=
            locate++;
            column++;
            type = 22;
            tempString = "<=";
          }
          else if (sourceChar[locate + 1] == '>')
          {
            //识别<>
            locate++;
            column++;
            type = 21;
            tempString = "<>";
          }
        }
        locate++;
        column++;
        break;
      }

      case '>':
      {
        if (locate != sourceChar.length - 1)
        {
          if (sourceChar[locate + 1] != '=')
          {
            //识别>
            type = 23;
            tempString = ">";
          }
          else
          {
            locate++;
            column++;
            type = 24;
            tempString = ">=";
          }
        }
        locate++;
        column++;
        break;
      }

      case '=':
      {
        type = 25;
        tempString = "=";
        locate++;
        column++;
        break;
      }
      case '#':
      {
        type = 0;
        tempString = "#";
        column++;
        locate++;
        break;
      }
      case ';':
      {
        type = 18;
        tempString = ";";
        column++;
        locate++;
        break;
      }
      default:
      {
        //如果是空格
        if (sourceChar[locate] == ' ')
        {
          //对type＝100为不做任何处理，只移位置
          type = 100;
          locate++;
          column++;
        }
        //如果是换行符
        else if (sourceChar[locate] == '\n' || sourceChar[locate] == '\r')
        {
          //对type=100为不做任何处理
          tempString = "";
          type = 100;
          column = 1;
          row++;